The Biomechanics Laboratory continues to develop and test techniques designed to explore the complex relationship between impairments of the neuromusculoskeletal system, functional limitations, and disability. One study of 18 normal subjects investigated the effect of dramatically different walking speeds on the mechanics of walking. Through the use of mechanical power analysis, it was demonstrated that two modes of walking may exist rather than a continuum of a single walking strategy. Another study evaluated a new technique for determining the role each major muscle group of the lower extremity plays in providing support to and propulsion of the body during walking. The results indicate forward progression was produced primarily by the ankle plantar flexors with a significant assist from the knee extensors. The results of these studies suggest that a complete and numerically consistent mechanical characterization of human movement is feasible. The application of these analytic techniques to the evaluation of human motion will have implications for rehabilitation and surgical treatment in patient populations.